I've been on a search for the perfect pillow and I have a Molecule mattress topper I like, so I decided to try their pillows. These in particular are stuffed with material in particulate and you can upzip the pillow to take some material out, so it's as thick or thin as you'd like. My problem with the pillow is that some of the material is not soft--there are little bits of material that make a crunching sound like paper which I find very strange for a pillow. When I took some material out they were little bits of thin plasticky material that bulked up the pillow but that made the pillow...loud. It's actually weirdly comfortable, but I took 2 stars off because my pillow is loud, haha. If you are looking for the perfect pillow, I might pass on these, sadly :(